Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932210AbZAOXqA (ORCPT ); Thu, 15 Jan 2009 18:46:00 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1765008AbZAOXpT (ORCPT ); Thu, 15 Jan 2009 18:45:19 -0500 Received: from kroah.org ([198.145.64.141]:33560 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1756192AbZAOXpP (ORCPT ); Thu, 15 Jan 2009 18:45:15 -0500 Date: Thu, 15 Jan 2009 15:44:04 -0800 From: Greg KH To: Trilok Soni Cc: Arve =?iso-8859-1?B?SGr4bm5lduVn?= , Alan Cox , Pavel Machek , Brian Swetland , arve@google.com, San Mehat , Robert Love , linux-kernel@vger.kernel.org, "linux-omap@vger.kernel.org" , Tony Lindgren , ext Juha =?iso-8859-1?B?WXJq9mzk?= , viktor.rosendahl@nokia.com Subject: Re: lowmemory android driver not needed? Message-ID: <20090115234404.GA20142@kroah.com> References: <20090114021801.GA14759@bulgaria.corp.google.com> <20090114035237.GB16442@kroah.com> <20090114104307.GA20451@elf.ucw.cz> <20090114104834.18387fca@lxorguk.ukuu.org.uk> <20090114231739.GB24111@kroah.com> <20090115001224.GC11328@kroah.com> <5d5443650901150532r20a4c25q834afadde2f98a3@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <5d5443650901150532r20a4c25q834afadde2f98a3@mail.gmail.com> User-Agent: Mutt/1.5.16 (2007-06-09) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2015 Lines: 44 On Thu, Jan 15, 2009 at 07:02:48PM +0530, Trilok Soni wrote: > Hi Greg, > > On Thu, Jan 15, 2009 at 5:42 AM, Greg KH wrote: > > On Wed, Jan 14, 2009 at 03:32:38PM -0800, Arve Hj?nnev?g wrote: > >> On Wed, Jan 14, 2009 at 3:17 PM, Greg KH wrote: > >> >> We actually use 6 different thresholds for killing processes. I don't > >> >> know what all the classes are, processes with a higher oom_adj value > >> >> can be killed with less impact to the user than processes with a lower > >> >> oom_adj value. The first few classes only affect latency when > >> >> switching apps, but later classes stop non critical background > >> >> services and finally the foreground app. Another reason to not kill > >> >> every process at the same threshold is that memory may not be free > >> >> immediately when the process is killed. > >> > > >> > But the lowmemorykiller android module doesn't have anything to do with > >> > this, right? > >> > > >> > >> It does. We write the thresholds to > >> /sys/module/lowmemorykiller/parameters/adj and > >> /sys/module/lowmemorykiller/parameters/minfree then set the oom_adj > >> value per process. If the standard oom killer can be adjusted in a > >> similar way, then we will not need the lowmemorykiller module. > > > > Great, care to document this somewhere so people like me don't get > > confused? > > And there is one more lowmem driver developed by Nokia for Nokia 8xx > tablets it seems. CCed Tony Lindgren, Juha and Viktor. > > http://git.kernel.org/?p=linux/kernel/git/tmlind/linux-omap-2.6.git;a=blob;f=security/lowmem.c;h=ae78a530af39703e335ad769f1e6f097f63ec6dd;hb=HEAD As we can't stack LSMs, using the lsm interface for a simple memory driver seems pretty wasteful :) thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/